Great Hill Pond, Portland
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Great Hill Pond is a 76-acre body of water in Portland, CT.   It is an artificial lake fed by the Great Hill Pond Brook. It has a 10-foot dike at the south end. Its only public access is a carry-in boat launch with minimal parking.   On average the pond is 5.5 feet deep, and reaches a maximum of 9 feet in a small area to the south.  During our survey in August 2006, 19 aquatic species were collected, including the invasive species Cabomba caroliniana (fanwort).  At this time, the beach was closed due to high levels of fecal coliform, and it was noted that all of the houses use septic systems.

Starting from the boat launch in the middle of the eastern shore and moving North, there are sizeable patches of Vallisneria americana (eel grass) and the invasive Cabomba caroliniana.  The Northeast cove has a large amount of Cabomba caroliniana, both by itself and underneath Nymphaea odorata (white water lily).  There are also patches of Brasenia schreberi (watershield), Nuphar variegata (yellow water lily) and Nymphaea odorata close to the shore.  Also in this cove are small amounts of Gratiola aurea (golden hedge-hyssop), Sagittaria sp. (arrowhead), Elodea nuttallii (western waterweed), Eleocharis acicularis (needle spikerush), Potamogeton epihydrus (ribbon-leaf pondweed), and Utricularia radiata (floating bladderwort).

Along the Northern shore is abundant Vallisneria americana with some Utricularia gibba (humped bladderwort) and Potamogeton epihydrus.  Further West is a large area with all of the floating species, as well as a small area of Cabomba caroliniana, Potamogeton epihydrus and Vallisneria americana . 

The sheltered, brook-fed cove to the Northwest is completely filled with vegetation.  The mouth of the brook has  Sparganium sp., Nuphar variegata, Nymphaea odorata, and Brasenia schreberi.  The mouth of the cove has a large area of Potamogeton pulcher (spotted pondweed) intermingled with Cabomba caroliniana. 

Moving down the western shore, there are several small patches of Nymphaea odorata, as well as abundant Vallisneria americana, and a single patch of Cabomba caroliniana.  The western shore also contains very small patches of all species listed below.  This mix continues down around the south-eastern shore.

The western-most inlet contains more Cabomba caroliniana, as well as a very diverse, dense mixture of all of the lake’s plants.  Recreation is only compromised in the two northern-most coves, where large patches of floating species may interfere with boating enjoyment.

Find Common Plant Names

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Species recorded in our 2006 survey of Great Hill Pond. Click on plant to view herbarium mount (invasive species in bold).

Brasenia schreberi


Cabomba Caroliniana

Elatine minima

Eleocharis acicularis

Elodea nuttallii

Gratiola aurea

Nuphar variegata

Nymphaea odorata

Potamogeton epihydrus

Potamogeton pulcher

Potamogeton pusillus

Ranunculus longirostris

Sagittaria sp.

Unidentified sedge

Utricularia gibba

Utricularia purpurea

Utricularia radiata

Vallisneria americana

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